simplify staking with Easy* class

packages/ton/src/FluentStaker.ts

@@ -0,0 +1,111 @@
+type AsyncStep = () => Promise<void>
+
+/*
+ * FluentStaker simplifies the process of creating, signing, and broadcasting by
+ * method chaining.
+ *
+ * Example usage:
+ * const result = await new FluentStaker(StakerClass, { ... })
+ *  .buildStakeTx({ ... })
+ *  .sign({ ... })
+ *  .broadcast({ ... })
+ *  .exec();
+ *
+ *  In addition you can call .staker() to get the underlying staker instance
+ */
+export class FluentStaker<Inst extends object> {
+  instance: Inst
+  queue: AsyncStep[] = []
+  lastResult!: any
+  unsignedTx!: any
+  signedTx!: any
+  initPromise: Promise<void>
+
+  constructor (StakerClass: new (...args: any[]) => Inst, ...ctorArgs: ConstructorParameters<typeof StakerClass>) {
+    // setup staker class instance
+    this.instance = new StakerClass(...ctorArgs)
+    this.initPromise = (this.instance as any).init ? (this.instance as any).init() : Promise.resolve()
+
+    // return our Proxy to handle all chaining
+    return new Proxy(this, {
+      get: (target, prop, receiver) => {
+        const inst = target.instance as any
+        const name = prop.toString()
+
+        // allow build*() methods
+        if (name.startsWith('build') && typeof inst[name] === 'function') {
+          return (...args: any[]) => {
+            target.queue.push(async () => {
+              target.lastResult = await inst[name](...args)
+              target.unsignedTx = target.lastResult.tx
+            })
+            return receiver
+          }
+        }
+
+        // allow sign() method
+        if (name === 'sign' && typeof inst[name] === 'function') {
+          return (opts: any) => {
+            target.queue.push(async () => {
+              if (target.unsignedTx === undefined) {
+                throw new Error('No unsigned transaction found. Please call a build method first')
+              }
+
+              target.lastResult = await inst.sign({ ...opts, tx: target.unsignedTx })
+              target.signedTx = target.lastResult
+            })
+            return receiver
+          }
+        }
+
+        // allow broadcast() method
+        if (name === 'broadcast' && typeof inst[name] === 'function') {
+          return (opts: any) => {
+            target.queue.push(async () => {
+              if (target.signedTx === undefined) {
+                throw new Error('No signed transaction found. Please call sign() first')
+              }
+              target.lastResult = await inst.broadcast({ ...opts, signedTx: target.signedTx })
+            })
+            return receiver
+          }
+        }
+
+        // exec() method to run all queued steps
+        if (name === 'exec') {
+          return async () => {
+            // initialize staker class instance
+            await target.initPromise
+            // then run build/sign/broadcast steps
+            for (const step of target.queue) await step()
+
+            // clear the queue
+            target.queue = []
+
+            // return the result to the caller
+            return target.lastResult
+          }
+        }
+
+        // staker() method to return the underlying instance
+        if (name === 'staker') {
+          return () => {
+            return target.instance
+          }
+        }
+
+        throw new Error(`Method ${name} not found. Please call build*(), sign() or broadcast() methods only.`)
+      }
+    })
+  }
+}
+
+// helper to auto-make these Easy classes
+export function makeEasyStaker<SC extends new (...args: any[]) => any> (StakerClass: SC) {
+  type Inst = InstanceType<SC>
+  return class EasyStaker extends FluentStaker<Inst> {
+    constructor (...args: ConstructorParameters<typeof StakerClass>) {
+      super(StakerClass, ...args)
+    }
+  }
+}

packages/ton/src/index.ts

@@ -14,3 +14,13 @@ export {
   NominatorInfo,
   TonTxStatus
 } from './types.d'
+
+// easy staker classes
+import { makeEasyStaker } from './FluentStaker'
+import { TonPoolStaker } from './TonPoolStaker'
+import { TonNominatorPoolStaker } from './TonNominatorPoolStaker'
+import { TonSingleNominatorPoolStaker } from './TonSingleNominatorPoolStaker'
+
+export const EasyTonPoolStaker = makeEasyStaker(TonPoolStaker)
+export const EasyTonNominatorPoolStaker = makeEasyStaker(TonNominatorPoolStaker)
+export const EasyTonSingleNominatorPoolStaker = makeEasyStaker(TonSingleNominatorPoolStaker)